Most Old World Warblers are of generally unseparate appearances. The sexes are often identical. However, some may be different, especially in the genus Sylvia. They are of small to medium size, from 9 to 16 centimeters in length. Their bills are small and pointed. Almost all species are mostly insectivorous. However, some will also eat fruit, nectar, or small seeds.[1]

Most of the species are monogamous and build simple, cup-shaped nests in plants. They lay between two and six eggs each time, depending on species. Both parents help in raising the young, which are able to fly at around two weeks of age.[1]